Cargo handled at state-owned piers declined 3 percent, to less than 1.3 million tons, during the first three months of the year, the Maryland Port Administration reported yesterday.

Despite the decline, state port officials remained convinced that Baltimore has become more competitive with other ports, and they predicted that tonnage will increase this year.

Much of that confidence comes from statistics showing that for the first time in years, Baltimore's share of the market is growing compared with those of three competing ports, Hampton Roads, Va., Philadelphia and New York.

Baltimore had a 13.8 percent share in 1991, almost a percentage point more than in 1990. Baltimore had been steadily losing market share in recent years, falling from 16.6 percent in 1987 to 12.9 percent in 1990.

"If you look at the port as a whole, we're gaining market share," said Adrian G. Teel, executive director of the Maryland Port Administration. "Our feeling is we did fine; we got our share."

The Virginia ports, however, continued to outpace Baltimore during the first quarter, posting a 4.4 percent gain, with slightly more than 2 million tons.

Mr. Teel said he expected the port of Baltimore's market share and tonnage to increase this year. "I believe when we get to the end of this year, we're going to do well compared to our competing ports," he said.

The port's biggest drop in the quarter came in steel shipments, which fell by 28,000 tons, a decline of more than 38 percent. Mr. Teel noted that Baltimore was not the only port to suffer a dramatic decline in that category. "Steel is in the bag for every port, not just us," he said.

The other big drop came in containers, which were off by about 25,000 tons, a decline of 2.7 percent.

Port officials attributed most of that decline to the decision of a major steamship line, Hapag-Lloyd, to drop Baltimore as a port of call last year. But Mr. Teel said he expects the port to recoup that loss. "I feel confident there are going to be some additional [steamship line] services to Baltimore," he said.

The quarterly statistics had bright spots. Automobiles moving through the port were up 4.8 percent, to 81,000 tons. That should help to solidify Baltimore's position as the No. 1 car port on the East Coast and the No. 2 in the nation.

In 1991, Los Angeles was the leader with slightly more than 1 million tons. Baltimore handled 626,000 tons. Jacksonville, Fla., was third with 497,000 tons.

The MPA also reported improvement in its financial condition. For the first nine months of the fiscal year, the port agency reported net income of $608,000. Last fiscal year, the MPA had a deficit of $2.8 million.

Capt. Michael R. Watson, president of the Association of Maryland Pilots, agreed with Mr. Teel that the port is on the upswing. The pilots, he said, saw a 10 percent increase in the number of ships calling at the port during the first quarter.

"This recession has been bad; it still is bad," he said. In spite of the difficult economic conditions, "Baltimore is holding its own well."

The port agency's statistics do not include traffic at private facilities, such as coal piers and grain elevators. Many of those terminals, particularly the coal piers, are busier this year than last, he said.